I was replying various times on a previous thread on what the hypothetical but likely Planet Nine should be called, and many people agreed on the consensus of "Persephone" or "Rupert" as good names. We had some own weird suggestions too. My own weird suggestions were "Ghost Zone" and "Arnold Perlstein". But I now have a new suggestion: Urania or Ourania. And I'm going to proceed to write a full-on essay on why Urania and Ourania are the best names. There is only one problem with my suggestion: Urania is already taken by the asteroid 30 Urania. But yet again, many people were fighting in that thread on why Planet Nine should be named Persephone despite asteroid #399 being named that already. Hopefully the IAU will allow an exception, but if not, that's why I've also suggested the Greek form, Ourania. Urania or Ourania, in Greek mythology, is the muse (the Muses are, in Greek mythology, the inspirational goddess of the sciences and arts) of astronomy, usually depicted with a ball representing the heavens in her hand and said to base conclusions by looking at the movement of the stars. Basically, the Greeks thought that Urania inspired them to study astronomy, which is exactly how Planet Nine came to be theorized - through mathematical calculations and orbital observation rather than direct observation of the planet itself. It also fits Planet Nine's position in our Solar System - near the very edge, the closest to the other "fixed" (not) stars, and with them always visible on its night skies. The motivation to name Planet Nine "Ourania" is parallel to choosing "Arrokoth" for 2014 MU69: "[it] reflects the inspiration of looking to the skies, and wondering about the stars and worlds beyond our own." So obviously, why shouldn't a planet in our Solar System be named after a goddess who promoted astronomy? As a person who studied astronomy since a young age, I sometimes think of Urania as my second mother. The name "Urania" also sounds like a feminine counterpart of "Uranus" - Planet Nine is estimated to be 10 Earth masses, which is just 4 few of the mass of Uranus (Neptune is more massive). Of course, Urania is a female. It should be noted that only one of the planets - Venus (if you don't count Earth as Terra or Gaia) - is named after a female! Thus, we need one more planet named after a goddess to balance the genders further or "cancel out" the male deity-dominated Solar System. (I know this sounds feminist, but still... and besides, I know the first asteroids - 30 Urania - are named after females, but still, legitimate planets) There is good news for Christians too: Urania, because of her name and being descended from the Greek personification of the sky (her name meaning "of heaven"), is sometimes associated with the concept of universal love (which could serve as a reminder for our war-ridden world to show love and dignity towards all human races - "Pax" after peace was voted the second-most popular name for Eris), or even the Holy Spirit, which is regarded by some Christians as even feminine. So Christians might see the planet as being associated with one of the three aspects of their god. And even though they believe in hell (i.e. Persephone), they probably don't want a planet in space ("heaven") to be associated with hell. Last of all, if we pick the more-Greek "Ourania" instead, even though this is for Michael E. Brown and Konstantin Batygin's Planet Nine from 2016, it alludes to William Henry Pickering predicting a planet called "Planet O" for Neptune (after "N", i.e. Neptune, "O" for Ourania) and later planets P, R, S, T, and U! So to conclude, I have listed down various reasons to argue why Planet Nine should be named Urania or Ourania. So what do you think? Should Planet Nine be called Urania? Ourania? No? Anything else? Reply below. I might email this essay to the IAU to see what their thoughts are. Addendum. Another reason to pick Ourania over Urania is to distinguish "Ouranian" from "Uranian" for Uranus. Perhaps the latter could become "Uranean" (only in that linked source).